Preservation of phenolic compounds on dried leaf infusion of Bauhinia forficata Link

Abstract Bauhinia forficata Link aqueous extract is usually recommended as a phytomedicine to reduce blood glucose levels and its biological activity has been linked to the presence of phenolic compounds from B. forficata preparations. Several drying processes are used in the production of dry herbal extracts, which may influence the chemical composition and efficacy of final herbal medicines. Due to significant chemical changes, defining appropriate drying processes is essential for phytopharmaceutical drug development. In view of this, we analyzed dried B. forficata leaf infusion (BFLI) extracts by HPLC-UV-MSn, followed by molecular networking analysis to evaluate the chemical profiles from dried extracts yielded by freeze-and spray-drying processes. The main metabolites detected included 11 ferulic/isoferulic acid derivatives and 13 glycosylated flavonoids. The qualitative chemical profiles were alike for both drying processes, whereas the relative abundance of some flavonoids was higher using spray-drying. Taken together, our results showed that freeze-and spray-drying preserved the phenolic profile of BFLI and suggested that spray-drying may be the most suitable to obtain its dried products. Along with studying the chemical profiles of dried herbal extracts, evaluating the influence of drying processes on the quality and chemical profiles of final products is pivotal and may benefit future research.

Genetic diversity and verbascoside content in natural populations of Pyrostegia venusta (Ker Gawl.) Miers.

BACKGROUND: Pyrostegia venusta (Ker Gawl.) Miers occurs in threatened biodiversity hotspots of Cerrado and Atlantic forest biomes in Brazil and is used in traditional medicine to treat various respiratory and skin diseases. METHODS AND RESULTS: This study (i) examined the genetic diversity and structure of six natural populations of P. venusta from different Brazilian regions using sequence-related amplified polymorphism (SRAP) markers; and (ii) compared the intra- and inter-populational levels of the bioactive component verbascoside using high-performance liquid chromatography. The population from Nova Mutum, Mato Grosso, presented the highest genetic variability (Nei index H = 0.2759; Shannon index I = 0.4170; 85.14% polymorphic loci), whereas the population from Araxá, Minas Gerais, presented the lowest genetic variability (H = 0.1811; I = 0.2820; 70.27% polymorphic loci). The intra-populational variability (79%) was significantly higher (p = 0.001) than the inter-populational variability (21%). The populations were clustered into two groups but their genetic differentiation was not associated with geographical origin (Mantel test, r = 0.328; p > 0.05). The verbascoside content significantly differed (p > 0.05) among the six populations and between the individuals from each population. The highest verbascoside levels (> 200 µg/mg extract) were detected in populations from Araxá and Serrana, while the lowest verbacoside levels were detected in populations from Paranaíta and Sinop. CONCLUSIONS: This is the first report on the use of SRAP markers to analyze genetic variability in the family Bignoniaceae. Our findings shall help to better understand the genetic and chemical diversity of P. venusta populations, as well as provide useful information to select the most appropriate individuals to prepare phytomedicines.

Atividade antibiofilme de substâncias de Croton urucurana em Staphylococcus aureus isolado de mastite bovina / Antibiofilm activity of Croton urucurana compounds against Staphylococcus aureus isolated from mastitis in dairy cattle

A mastite bovina é a enfermidade que causa maior impacto na produção leiteira, sendo o microrganismo Staphylococcus aureus o mais prevalente. Este gênero possui a capacidade de produzir biofilmes que é um importante mecanismo de resistência aos antibióticos. Considerando a capacidade terapêutica das plantas, a espécie Croton urucurana, nativa do Cerrado, foi alvo do presente estudo, que teve como objetivo avaliar a atividade antibiofilme in vitro do extrato vegetal e substâncias isoladas desta espécie, frente Staphylococcus aureus, isolados de leite de vacas com mastite, bem como dos antibióticos gentamicina e vancomicina. A atividade antibiofilme foi avaliada por meio do cristal violeta e da contagem de unidades formadoras de colônia. As imagens foram obtidas por microscopia eletrônica de varredura. O extrato bruto e frações de C. urucurana apresentaram atividade antibiofilme superior à gentamicina e semelhante à vancomicina, enquanto a substância isolada α-Costol foi significativamente mais ativa quando comparada aos demais tratamentos avaliados, reduzindo cerca de 6 ciclos logarítmicos da população bacteriana em biofilme. Conclui-se que os fitocomplexos e a substância α-Costol isolados de Croton urucurana são promissores no combate a um dos principais agentes etiológicos da mastite bovina.(AU)

Mastitis in dairy cattle is the disease that impacts dairy production the most; Staphylococcus aureus is the main causative agent of this condition. The genus Staphylococcus has the ability to produce biofilms, an important mechanism of antibiotic resistance. Bearing in mind that plants have therapeutic action, this study investigated the in vitro antibiofilm activity of the plant extract and compounds isolated from the species Croton urucurana, native to the Brazilian Cerrado, against Staphylococcus aureus isolated from the milk of cows with mastitis, as well as the antibiotic gentamycin and vancomicyn. The antibiofilm activity was evaluated by means of violet crystal and the counting of Colony Forming Units. The images were obtained by scanning electron microscopy. The C. urucurana crude extract and fraction displayed better antibiofilm effect than gentamycin; their antibiofilm action was similar to the action of vancomycin. Compared with all the assessed treatments, the isolated compound α-Costol was significantly more active it reduced six logarithmic cycles of the bacterial population composing the biofilm. The phytocomplexs and the α-Costol substance isolated from Croton urucurana are promising in the fight against one of the main etiological agents of bovine mastitis.(AU)

Eugenia punicifolia (Kunth) DC. as an adjuvant treatment for type-2 diabetes mellitus: a non-controlled, pilot study.

Type-2 diabetes mellitus (DM) is a highly prevalent disease with significant morbidity and mortality around the world. However, there is no universally effective treatment, because response to different treatment regimens can vary widely among patients. In this study, we aimed to investigate whether the use of the powdered dried leaves of Eugenia punicifolia (Kunth) DC. (Myrtaceae) is effective as an adjuvant to the treatment of patients with type-2 DM. Fifteen patients were enrolled in a pilot, non-controlled study, and received E. punicifolia for 3 months. After treatment, we observed a significant decrease in glycosylated hemoglobin, basal insulin, thyroid-stimulating hormone, C-reactive protein, and both systolic and diastolic blood pressure. There were no changes in fasting and postprandial glycemia. The compounds myricetin-3-O-rhamnoside, quercetin-3-O-galactoside, quercetin-3-O-xyloside, quercetin-3-O-rhamnoside, kaempferol-3-O-rhamnoside, phytol, gallic acid, and trans-caryophyllene present in the powdered dried leaves of E. punicifolia may be responsible for the therapeutic effect. In conclusion, the powdered leaves of E. punicifolia are promising as an adjuvant in the treatment of type-2 DM and deserve further investigation.

Isolation of flavonoids from Anemopaegma arvense (Vell) Stellf. ex de Souza and their antifungal activity against Trichophyton rubrum

Anemopaegma arvense (Vell) Stellf. ex de Souza belongs to the family Bignoniaceae, and is popularly known as catuaba. To evaluate the cytotoxic and antimicrobial activity of A. arvense, fraction F3 and flavonoids 1 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside) (rutin) and flavonoid 2 (quercetin 3-O-α-L-rhamnopyranosyl-(1→6)-β-D-galactopyranoside) were isolated from the leaves of this plant. Fraction F3 and flavonoids 1 and 2 exhibited no antibacterial activity. Furthermore, no cytotoxic activity of fraction 3 or flavonoids 1 and 2 was observed against the tumor cells tested. However, analysis of the antifungal activity of flavonoids 1 and 2 revealed minimum inhibitory concentrations of 0.5 and 0.25 mg/mL, respectively, against the Trichophyton rubrum strains tested (wild type and mutant). This study demonstrates for the first time the antifungal activity of isolated flavonoids, validating the same activity for A. arvense.

Anemopaegma arvense pertence à família Bignoniaceae, sendo conhecida popularmente como Catuaba. Para avaliação de sua atividade citotóxica e antimicrobiana, a fração cromatográfica F3 e os flavonoides 1 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-glucopiranosídeo) (rutina) e flavonoide 2 (quercetina 3-O-α-L-ramnopiranosil-(1→6)-β-D-galactopiranosídeo) foram isolados das folhas de A. arvense. A fração 3 e os flavonoides não apresentaram atividade antibacteriana. Nenhuma atividade citotóxica foi observada para a fração F3 e para os flavonoides, quando avaliados contra as células tumorais em teste. Entretanto, e considerando a atividade antifúngica, o flavonóide 1 apresentou valor de concentração inibitória mínima (CIM) de 0,5 mg/mL, enquanto o flavonóide 2, CIM de 0,25 mg/mL contra as cepas selvagem e mutante de Trichophyton rubrum, demonstrando, pela primeira vez, que os flavonoides isolados possuem atividade antifúngica, o que valida a mesma atividade para A. arvense.

Detection of flavonoids in glandular trichomes of Chromolaena species (Eupatorieae, Asteraceae) by reversed-phase high-performance liquid chromatography

In this work, twelve flavonoids were detected in glandular trichomes of two species of Chromolaena through the glandular microsampling technique and HPLC-UV-DAD analysis. This is the first time that the accumulation of flavonoids in glandular trichomes of the genus Chromolaena is reported. Based on the results, we suggest that this technique can be an useful tool in the search of new compounds with medicinal properties as well as in chemotaxonomic studies of Eupatorieae.

Neste trabalho 12 flavonóides foram detectados nos tricomas glandulares de duas espécies de Chromolaena através do emprego da técnica de microamostragem de tricomas glandulares, associada à análise por CLAE. Esta é a primeira vez que se relata o acúmulo de flavonóides em tricomas glandulares no gênero. Com base nos resultados obtidos, podemos sugerir que esta técnica pode ser uma ferramenta útil na busca de substâncias com propriedades medicinais e em estudos quimiotaxonômicos de Eupatorieae.

Estudo fitoquímico de Mikania pseudohoffmanianna G. M. Barroso ex W. C. Holmes / Phytochemical study of Mikania pseudohoffmanianna G. M. Barroso ex W. C. Holmes

This work describes the fractionation of methanol and dichloromethane extracts of aerial parts from the Mikania pseudohoffmanniana G. M. Barroso ex W. C. Holmes. The phytochemical study of extracts led to isolation and the identification of 16 known compounds, including: steroids: campesterol, stigmasterol and 'beta'-sitosterol, diterpenes: ent-15'beta'-E-cinnamoyloxy-kaur-16-en-19-oic acid, ent-15'beta'-Z-cinnamoyloxy-kaur-16-en-19-oic acid and ent-kaur-16-en-19-oic acid, triterpenes: 'alpha'-amyrin, 'beta'-amyrin, 'alpha'-amyrin acetate, 'beta'-amyrin acetate, lupeol, lupeol acetate and friedelin, coumarin: scopoletin, flavonoid: quercetin and caffeoyl quinic acid derivative: 4,5-di-O-[E]-caffeoyl quinic acid

O fracionamento dos extratos diclorometânico e metanólico das partes aéreas de Mikania pseudohoffmanniana G. M. Barroso ex W. C. Holmes resultou na identificação de 16 substâncias: os esteróides: campesterol, estigmasterol e b-sitosterol; os diterpenos: ácido ent-15b-E-cinamoiloxi-caur-16-en-19-óico, ácido ent-15b-Z-cinamoiloxi-caur-16-en-19-óico e ácido ent-caur-16-en-19-óico; os triterpenos: a-amirina, b-amirina, acetato de a-amirina, acetato de b-amirina, lupeol, acetato de lupeol e friedelina; a cumarina: escopoletina; o flavonóide: quercetina e o derivado do ácido cafeoilquínico: 4,5-di-O-[E] -cafeoilquínico

Antimicrobial activity of flavonoids and steroids isolated from two Chromolaena species

The crude extracts (dichloromethanic and ethanolic) and some compounds (8 flavonoids and 5 steroids) isolated from Chromolaena squalida (leaves and stems) and Chromolaena hirsuta (leaves and flowers) have been evaluated against 22 strains of microorganisms including bacteria (Gram-positive and Gram-negative) and yeasts. All crude extracts, flavonoids and steroids evaluated have been shown actives, mainly against Gram-positive bacteria